Gear changing apparatus



Sept. 15, 1931. R. M.- RUcK GEAR CHANGING APPARATUS Filed March 19, 19250 5 Sheets-Sheet MRM,

Filed March 19, 1930 5 Sheets-Sheet 2 sept. 15, 1931. R. M. RUCK 1,823,766

` GEARv CHANGING APPARATUS 'Filed March 19, 1930 5 Sheets-Sheet 3 Sept. 15, 1931. R. M. RUCK GEAR CHANGING APPARATUS Filed March 19, 1930 5 Sheets-Sheet Sept. 15, 1931. R. M. RUCK GEAR CHANGING APPARATUS Filed March 19, 1930 5 Sheets-Sheet.

Patented Sept. 15, 1931 i STA TES s RICHARD MATTHEWS BUCK, 0F LEAMINGTON, ENG-LAND GEAR CHANGING APPARATUS Appncanon inea ivrarci119,j193o, serial No. 437,189, and in Great Britain Marchv 25,` 1929.

This invention relates yto manually-controllable automatically-acting, power operated, step-by-step gearchanging apparatus vof the general type referred to in the specii'ication of Letters Patent No.l,6lly0,808, and it has for its primary object to provideyan improved and more compact construction such that, with tie exception ofthe handlever or' levers or equivalent devices for l manually initiating or effecting a change of gear, all the parts may be placed inside` the gearbox which latter will requireonly slight enlargement as compared with the gearboxes at present employed with anyof the Well-known type of change Aspeed inschanism.

In order to avoid needless repetition, -it will suiiice here to state that the more essential parts of the automatic mechanism defl scribed in the specii'icationvabove mentioned are retained in the improved construction of the present invention, the more important of these parts including what were therein referred to bythe following terms, namely Y l. A continuouslydriven cam-shaft ;V

2. A pair of roc ring-shafts extending parallel to and equidistant fromf said camshaft;

3. A pair of pawl-levers splined upon the respective rocking-shafts and adapted to be slidden along said shafts by cam action;

fl. Spring means tending to turn the rocking shafts from their normal orinoperative ngular position, and to retain the pawlev rs in ytheir normal or inoperative posiio s lengthwise of the rocking shafts;

o. A. pair of timing-levers fast on the respective rocking shafts; y

6. A pair of locking-levers normally spring-held in position to engage the timing-levers so as to prevent the rocking-shafts turning under the influence of their springs;

7. A timing-cam7 fast on the cam-shaft, for determining the moment at which each rocking-shaft may turn in either direction; and

8. A pair of locking cams fast on thecam-shaft for returning to normal angular position whichever timing-lever andk rockingshaft has been unlocked and released therefrom on the manualinitiation of an automatic change of gear. In place, however, of the pair of main cams fast on the cam shaft as in the said prior Letters Patent, only one main cam is required as both the pawl-levers7 in the present case, move in thesame direction.

According to the present invention, the

changes of gear are effected by means of av cylindrical cam, hereinafter termed the Selector-cam (or cams) rotatable about its axiswhich-extends parallel to that of the shaft' (or shafts) whereon are mounted the displaceable elements (e. g; clutch-members, slidable pinions, or the like) of the several transmission trains orgroups comprised in the gear-changing apparatus; the selectorcam (or cams) being engaged lby a series of arms, one for each such displaceable element, on as many slides, eaehof which has also an arm engaging one-of the displaceable ele-l ments. By this arrangement the employment l'of external selector-bars is dispensed with, and great compactness of construction is ensured. s

In addition,` the main slide, which in previous arrangements (as in the specification of Letters Patent No. 1,640,808) formed an important feature of the mechanism, is entirely omitted and the sliding movements imparted to the respective pawl-levers by the main cam are caused to impart step-by-step rot-ary movement in the one or the other direction to a star-wheel` fast on the shaft which carries the selector-cam (or cams)an arrangement by which still further simplification and compactness are attained.

One form of the invention will now lbe ldescribed by way of example, with referenceV to the accompanying drawings in which Figure l is a sectional elevation taken through the axis of a gear box in which the apparatus of the present invention is incor-` porated,

Figure V2 is a fragmentary sectional plan taken on the line 2-2 of Figure l; Figures 3 and 4 are perspective views of two, selec tor-cams, y

Figure 5 is a fragmentary sectional elevamovement imparted to the gear-changing slide (described hereinafter) kand the shootf ing into gear of thatl pinion (e. g. 620163) which is to be shifted (such lost motion being necessary in the event momentary failure in registration of gear teeth with tooth intervals in theeorresponding transmission train).

Each cam-groove 66, 67 formed in the selector-cams 64, 65 has an oblique or active portion 66, 67', and a straight circumferential or idle portion 66?, 672 (see Figures 3- and 4) these portions being so disposed around the axis of the kcams, in the case of the respective grooves, that the oblique or active portions 66, 67 of only one cam groove at a time can come into operation to shift the correspondingA pinion 62, 63 of the gear changing apparatus, the remaining 77, 78 formed with` arms 79, 80 adapted tov engage permanently the cam grooves inthe selector-cams 64, 65 said selector-operators 77, 78 being screwed to the selectors 31, 82 slidably mounted on gear-changing slides 83, 84, whilst the selectors 31, 82 are formed with arms (or preferably forked arms) 35, 86 permanently engaging a groove in the slidable pinions 62, 63.,4 The gear changing slides 83, 34 are lXedto the gear-,box casing and are` formed along their length witha series of circumferential depressions such as 87, 88, 89 forvthe. purpose of permitting a spring-pressed ball 90 carried in a recess 91 (which also retains the spring 92) formed in the selector 81, 32, to engage said depressions thereby acting as a lock or safety-catch or the selector to prevent actuation of the slidable pinions 62, 63 if the selectorcams 64, 65 be not operated.

In the drawings, only two slidable pinions are shown, this being the arrangement which can be adaptedvery readily for use with gear-,boxes known as the three-speed type and it will be understood that, if more speeds be required, the addition of further pinions (and consequently selector-cams) will be suflicient without alteration to the other parts of the apparatus.

1t will be understood that the main cam 53 is adapted to slide the one or the other pawl-lever 47, 43, 49 or 50, 51, 52, whichever has been angularly displaced by rotationof its rocking-shaft 36 or 37 along said shaft,

each through a predetermined distance during part of one revolution of the camshaft 21 and, during the remainder of such revolution, to permit the pawl-lever 47, 48, 49 or 50, 51, 52, to return to its normal position by a combined sliding and angularmove' ment. Consequently as the respective pawllevers are adapted to engage between adja cent teethV of the star wheel 54 from opposite sides, the operative sliding movement of the one pawl-lever imparts a step-bysteprotary movementto the star-wheel and hence to the selector-cams 64, 65, in one direction only,

- the other pawl-lever being adaptedto impart a similar movement to the selector-cams, but in the contraryV direction. A neutral position is provided between each two successive active positions of theY gear-changing apparatus, and, by bringing into loperation the one or the other pawl-lever, all available changes'of gear upwards `or downwards may be run through step-by-step, two complete steps (e. g. from rst gear to neutral and thence either to second gear or reverse gear,

at will) being required between any one active position and the next succeeding activey position of the 'gear-changing apparatus. -At the conclusion of each step all parts return automatically to normal position. f

In Yorder to lock the star-wheel 54 and hence the selector-cams 64, 65 against acci'- dental angular movement'a jumper in the rform of,l a ball 93 is carried in a cylindrical casing 94 bolted to the gear-box casing, the ball 93 being pressed outwardly from said cylinder, by a coiled spring 95, to engage between adjacent teeth of the star-wheel, the edgesof the star-wheelteetli being chamfered as at 96 to permit the ball 93 to slide thereover when a change in gear either upward or downward, is effected, (see Figure 5). A further lock forthe star-wheel and hence the selector-camsis provided to prevent, positively, any actuation thereof if an automatic changeof gear be notinitiated, this lock being dependent on the angular displacement of the rocking-shafts 36, 37. A. spring-pressed pin 97,` carried in a bracket 93, is adapted to engage one of a series of4 holes 99 formed in the face of the star-wheel 54 being maintained in such engagement by a strong leaf spring 100 secured at one end to the casing of the gear boX. The `rear end of the pin 97 is formed with two shoulders 101, V102 against which are adapted to bear from opposite sides the ends of two arms 103, 104

`each formed integrally with the collars 42,

43 s'plined on the rocking-shafts 36, 37 and serving as abutments for the thrust-springs 40, 41. It will be clear that when the one or the other rocking shaft 36 or 37 is angularly f cams 64, 65 to be free to rotate, apart from the restraining influence of the springpressed ball 93, under the sliding action of the one or the other pawl lever 47, 48, 49 or Manual initiation of Aan `automatically produced step in a change of gear kmay be effected by means somewhat similar to vthose zdescribed in the specification of my prior 10 spring 109 adjustable at 110, so as to cause ribs 111, 112 on the levers 105, 106 to engage notches V113, 114, on the hubs of a pair of timing-levers7 115, 116 which are fast on M the adjacent ends of the respective rocking ishafts'36, 37. The timing levers 115, 116

extend from their respective rocking-shafts towards one another in parallel planes and carry on normally coincident axes parallel with the axis of the cam-shaft 21, anti- `lfriction rollers 117, 118 each of which adapted, when the corresponding,timinglever 115 or 116 is released `by its lockinglever 105 or 106 to'move under the action ,of the spring 44. This spring 44, when thus "permitted to act, causes the rocking-Shaft or 37 to turn so as, on the one hand, to bring the arm 47 or 50 of the pawllever into engagement withthe main-cam .53, the arm 48 or 51 to engage between adjacent-teeth of thestar-wheel 54 the arm 49 or 52 to engage with the arm 56 or 57 yon the hubs 58er 59 mounted on the clutch-control shaft 60 and (d) to rocl the collar 42 or 43 thereby causing the arm 103 'or 104 to Withdraw the pin 97 from engagement with one of the series o-f holes 99 in the star-wheel 54 and, on the other hand, to bring the anti-friction roller 117 or 118 Ainto engagement with the edge of a lockingcam 119 or 120 whereby at the proper moment, the timing-lever 115 or 116, whichever has been depressed, is raised aoain to its normal position so as to restore to its normal .or inoperative angular position the particular rocking-shaft 36 `or 37 which has been allowed to turn and thus. to reset all the (1o-acting parts to normal position. u

The locking-cams 119, 120 which are of .similar shape and angularly coincident are fast, side-by-side,.on the camshaft 21, outside the bearing 22 and between them there is also fast upon the same shaft a timingcam 121 consisting of a disc from the opposite faces ofy which, throughout rather less than one half'the circumference, project a pair of similar and angularly coin: cident timing-flanges 122, 123. From those faces lof the timing-levers 115, 116 which are adjacent to the timing-cam 121,

project studs 124, 125 each of which, so long.

as its timing lever occupies its normal or inoperative angular position, remains outside the path of the corresponding timing-flanges 122, 123 but which, when said-timing-lever comes into operative angular position, is presented inside the path of the timingilanges 122, 123. The angular interval during which the timing-flanges are passing the studs 124, 125 coincides substantially with that portion vof a revolution of the camshaft 21 wherein the main-cam 53 can shift apawl-lever 47, 48, 49 or 50, 51, 52 lengthwise of its rocking-shaft 36 or 37 against the thrust of the coiled-spring 40 or 41, a distance equivalent to one step in the rotation of' thestar-wheel 54 in the one direction or the other and, during such interval, the individual timing-flanges 122, 123 so cooperate with the respective studs 124, 125 as either, on the one hand, to prevent the timing-levers 115, 116 from leaving their inoperative position or, on the other hand, to prevent whichever of said timing-levers (if either) has been brought to operative position, from being accidentally withdrawn therefrom.

Therelease of the respective timing-levers 115, 116 of the automatic mechanism (only one of which can be brought into operation at a time) is effected through the medium of a longitudinally movable releasing-link 126, extending transversely of both locking-l levers 105, 106 and which has'a p'in-and-slot or equivalent engagement with the respective locking-levers. As illustrated the releasing link 126, passes through, and is doubly shouldered at 127, 128 to engage projections 129, 130 on the respective locking levers. According, therefore, as the releasing-link 126 is moved in the one direction or the other from a mid or neutral position, the one or the other locking-lever' 105 or 106, depending on which shoulder 127 or 128 is caused to bear thereagainst, will be disengaged from the hub of the corresponding timing-lever 115 or 116 and will thus permit the corresponding gear-changing operation to take place, the other locking-lever being held, meanwhile by the action of the spring 109 against any tendency to be displaced.

The releasing link 126 is adapted to be moved in the one direction or the other at will, for vwhich Ypurpose it is attached to one end, by means of a suitable slot connection 133, with one end of an arm 134, pivoted as at 135 to the casing 25 of the gearbox, the other end 136 of said arm being adapted to engage a slot 137 formed'in a quadrant 138 fast upon a manually rotatable spindle 139, extending upwardly through the floor indicated as 140aA ofthemvehiclel` and terminating in convenient proximity tothe head of the steering column. According, therefore, as the spindle 139 isrotated in the ene direction or the other, the varm V.134, 136 Will be rocked to displace the yreleeasinglink 126 ina corresponding lirection, with the result that the locking-lever er 106 Will be disengaged from its timing-lever cr 116 to permit the corresponding change of gear te take place. Sleeved upon the manually rotatable spindle 139 is a. hollovvshaft140 fast upon the outer end 0f which is a control disc 141 over which a halid-lever4 Aor a serrated knob 142, fast upon the outer end of the spindle 139, is movable. Y

Fast upon the inner end of the hollowshaft'140 and in proximity to the quadrant' is a bevel gear-Wheel143 adapted tc mesh with a second bevel-gear-Wheel 144 fast upon the rear-end of the Vstar-Wheel shaft 55, se that when the hand-lever 142 has been moved to Vrotate the spindle 139 in the one direction or the other, thereby causing the releasing-link 126 to be movedin a corresponding direction'to release the one or the other locking-levers 105 or 106A and .se bring about the desired change in gear, up or down, the resulting rotary movement automaticallyinnaarted to the star-.vheel 54 star-Wheel shaft 55 and selector-cams 64, 65 Will be transmitted through the bevel gear-Wheels 144 and 143 to thehollow shaft and the second quadrant 141, which latter will thus be caused to return thehandlever 142 to its normal position and thus afford an indication of the completion of the gear-changing operation to the driver of the vehicle andthe gear-changeyvhichhas been effected. f i' Two modiiications of the hand-lever 142 are shown in Figures 7 Vand 8 respectively. In Figure 7 the hand-lever 142 is-in the form of a spring blade 1li-2a furnished ivith i r1; a control handle 145 movable over, and normally locked to, by means of the pin 146 on the arm 147 of the hand-lever, one of alcircular series of holes A148 formed in the second quadrant p (or control disc) 141 fast on the upper end of the hollow shaft 140 sure rounding the manually rotatable spindle 139, the number of holes148, ofcourse,1corre spending With the available number'ofgear positions.

Figure 8, the handeleverfis inthe form of a .serrated knob 149 fixed to the upper end of the manually rotatable spindle 139 and provided vvith a spring-loadedplunger in the form-of a ball 150 'pressed'outivardly from said knob by 'a spring 151`to interlock with any one of the series of holes 148 formed in the control disc 14 The knob 149 maybe provided with a pointer 149EL so that a moved in the same direction by rotation of VpaWl-lever is providedwithan arm 49, 52 which, as soon as the paWl-lever begins to yrockingshaft, projecting beyond the gear- In the second modification, as shown in yaliand-Wheel 152 (or--handlever), so that the hollow shaft and hence the bevel gear- Wheels 143,144 and the selectorecams 64, v65M may be rotated thereby etiiecting'the opera-75 tion of the selectorfoperator -77 or 78, the

lselector 81 or 82, and theslidable pinion^62 or 63 to producethe desired changein gear. When a change in gear is keffectedin this manner, it is necessary to release the star- Q80 Wheel shaft 55 (and'hence the selector-cams @64, 65) to be free to rotate, by withdrawing the locking-pin 97 engaging one of the circular series of holes 99 formed in the star-r1 Wheel 54 and for this purpose a Bovvden85 Wire connection is provided to Withdraw the pin 97 against'the thrust of the spring 100 before the khand-Wheel "152 is 'rota-ted to effect a manual' change in gear.

It is desirable, in cases Where the drive is transmitted through a friction clutch, as is' general in automobile practice, to arrange for the clutch to be disengaged before the actual commencement of a change ingearM When it is effected'automatically. This au- `95 tomatic disengagement of the clutch may be accomplished very readily by the apparatus of the present invention, for since both paWl-levers 47, r48, 49 and 50, 51, 52 are the main' cam 53, suchv movement can be utilized to bring about the disengagement of the clutch. As referred to above, each "105 slide along its rocking-shaft 36, 37 to effect a change in gear againstthe thrust ofthe coiledspring 40, 41, engage With an arm 5 6,

57 formed on ahub 58, 59 splined on the clutch-control-shaft 60, and thus imparts an k1-10 angular movement to said shaft.

The clutch-control-shaft 60 extends transversely of, but notin the same plane as, the

box and has on its outer end an arm 153 to 115 Which is secured a link or chain 154 secured at its other end to one arm 155 of a bellcrank lever,theother arm 156 of which is secured to the moveable members 157 of the driving clutch.A Thus'the angulardisplacement of the one or the other rcckingsshaft` to effect a change in gear, rup or down, actu* ates the clutch-controlshaft to Withdraw the clutch before the actual change in ythe apparatus commences.

It Willbe understood that the Whole of the mechanism described, with the exception vo the hand-lever` (or serrated knob) for initiatingv an automatic change of gear .and thehand-Wheel (or hand-lever for ef- 4130 being fecting a change of gear manuallyfcan be accommodated within a gear-box very little larger than those at presentl employed to house a set of speed changegeari'ng of any of the well-known types.

The method shown for driving the camshaft is given by way of example only, it understood that anyA convenient method may be employed (provided that the camshaft is rotating continually as long yas the engine is ruiming) and that different methods of drive may be necessary for differentA types of speed change mechanism.

I claim l. Gear-changing mechanism for a vehicle comprising a plurality of cylindricalV cams,

Va shaft therefor. a pair of pawl-levers, each mounted on a rocking-shaft, arms on said paWl-levers a main-cam fast on a cam-shaft driven continuously by the engine, a starwheel fast on the shaft on which said cylindrical cams are mounted, means for rocking the one or the other of said pawl-levers firstly to cause one of said arms thereon to engage between adjacent teeth of said starwheel and secondly to cause a second of said arms thereon to engage the face of said main cam to be slidden a distance corresponding with the pitch of the teeth on said stai--wlieel along saidY rocking shaft to impart a rotary motion to said Ystar-wheel equivalent to the angular pitch of said starwheel.

2. Gear-changing mechanism for a vehicle, comprising a plurality of cylindrical cams, a shaft, a pair of pawl-levers each mounted on a rocking-shaft, three arms formed on said pawl-levers, asinain-cami fast on a cam-shaft driven continuously by the engine, a star-wheel fast on the shaft on which are mounted said cylindrical cams, a

clutch control shaft, an arm on said clutch! controlshaft, means for rocking the one or the other of said pawl-levers so that, when the one or the other of said pawl-levers is rocked, the rst engages the face of said main-cani, the 'second engages between two adjacent teeth on the star-wheel so that the Vsliding movement imparted to the pawllever by the engagement of the first arm with the main cam imparts a rotational movement to said star-wheel and the third arm engagessaid arm projecting from said clutch control shaft so that the clutch may be withdrawn automatically immediately before a change in gear is effected.

3. Gear changing mechanism for avehicle as claimed in claim 2 wherein the pawl-levers are retainedin their normal inoperative position and returned to such position after the one or the other has been displacedlain gularly as the result of a manual operation on the part of the driver of the vehicle,

4. Gear-changing mechanism for a vehicle comprising` Va pair of paWl-levers each mounted on a rocking-shaft, means for rocking lthe one or the other of said pawl-levers, a star wheel, means for locking said starvwheel positively against angular displaceshoulders on said pin adapted to be engaged by each of said arms from opposite sides, said pin being adapted to be withdrawn against the thrust of a spring on the manual initiation of an automatic change in gear.

5. Gear-changing mechanism for a vehicle as claimed in claim l, wherein the star-wheel is locked against accidental angular displacement by means of a spring-pressed jumper engaging between two adjacent teeth on said star-Wheel.

6. lGear-changing mechanism for a vehicle comprisingk a pair of pawl-levers each mounted on a rocking-shaft, a releasing link a pivoted lever a quadrant fast on a manually rotatable spindle extending upwardly through the floor of the vehicle and terminating in proximity to the head of the steering column, a slot formed in said quadrant, the one arm of said pivoted lever engaging said releasing link and the other arm engaging said slot formed in said quadrant, actuation of said quadrant in the one direction or the other effecting a corresponding movement of said releasinglink which in turn rocks the one or the other pawl-lever to effect an automatic change in gear.

7. Gear-changing mechanism for a vehicle as claimed in claim 6, comprising a starwheel a shaft therefor, a manually rotatable spindle on the lower end of which is mounted said slotted quadrant, a hollow shaft sleeved upon said manually rotatable spindle, a second quadrant (control disc) fast on the upper end of said hollow shaft, a hand lever fast upon the outer end of said manually rotatable spindle movable over said second quadrant, a bevel gear-.wheel on the other end of said hollou7 shaft and in proximity to the slotted quadrant fast on the inner end of said manually rotatable spindle, a second bevel gear-wheel fast on said star-wheel shaft and in mesh with said first gear-wheel so that when a change in gear is effected (i. e. by rotationof said starwheel shaft) the hollow shaft and hence the second quadrant, (control disc) will be forced to return the hand-lever or the like 'to its normal position with respect to the secondquadrant and thereby afford an indication of the completion of the gear-changing operation and-the change in gear which has been effected.V Y

RICHARD MATTHEWS RUCK. 

